"What are you doing Dan?"
My roomate, Bill, was picking cut blades of grass out of his hackey sack before he brushed his teeth for bed. He looked me over nonchalantly at first, then with increasing curiosity.
"Trying to fall asleep standing on my head." which was easier said than done. One I was more or less on my head, it got harder and harder to relax by the second.
"Why are you doing that though?"
"I'm going to try something new every day. I don't think this is going to work, but at least I tried, right?"

When people ask me "Why are you learning to fire dance?" my response is often "If you could, wouldn't you?". It's surprising how many people have told me they wouldn't.